When Mannion returns to Washington, D.C. to get his job back, he must work outside the system to clear Temple of a murder charge.
When the new police chief is responsible for a drug raid that causes a woman's death, Mannion sees a chance to get his old job back.
Mannion tries to get his ex-wife to work for him; Temple suspects some officers of police brutality and sets a trap for them; when a parolee is mudered, Mannion takes action.
When an Internet predator convinces Noland's niece to run away the team must search for her.
A local community becomes fed up with the justice system and forms their own underground street justice; Mannion searches for the person who received Ella's heart.
Mannion investigates a murder that has similarities to a string of murders comitted by a serial killer 20 years prior.
Mannion investigates a man's death after he is killed during a civil war re-enactment.
Mannion vows to take down drug trafficking in Washington after Ella's son is hospitalized for taking ecstasy.
When a vision of the Virgin Mary appears on the side of Mannion's building, a thief decides to start giving away his loot to the needy.
Mannion enlists the help of a former hostage negotiator in order to get through to an autistic girl who witnessed her parents' murder.
When Mannion investigates a gay police officer hit by a car, he suspects that another policeman refused to give mouth-to-mouth resuscitation.
Mannion investigates the death of a congressional lobbyist who, prior to her death, was on the verge of exposing a scandal involving the exchange of sexual favors for votes.
When a crime lord's henchman targets a former stripper on a list of possible witnesses, Mannion must try to protect her from the same fate as another murdered trial witness.
Mannion probes the death of Ella's uncle, a prime suspect in the unsolved murder of a jazz singer.
Mannion's fencing teacher tells him that she killed her husband in self defense, but the evidence proves to be inconclusive.
Mannion, Regan and Debreno search for a 6-year-old girl snatched from a playground.
When Mannion goes to a small town to protest a warrant for his arrest, he ends up involved in a murder investigation; an armored truck disappears from the company that Temple works for part time.
Noland's battle against gangs results in his being shot and critically wounded.
Mannion investigates the murders of two women and finds out that one of the victims is Debreno's sometimes girlfriend.